/Engine/Source/Runtime/RenderCore/Public/RenderGraphBuilder.h
Register an external buffer with a custom name. The name is only used if the buffer has not already been registered.
FRDGBufferRef RegisterExternalBuffer ( const [TRefCountPtr](API\Runtime\Core\Templates\TRefCountPtr)< [FRDGPooledBuffer](API\Runtime\RenderCore\FRDGPooledBuffer) > & ExternalPooledBuffer, const TCHAR * NameIfNotRegistered, ERDGBufferFlags Flags )